This application is based upon and claims the benefit of priority from the prior Japanese Patent Application No. 11-175480, filed Jun. 22, 1999, the entire contents of which are incorporated herein by reference.
The present invention relates to an improvement of an electronic camera for compressing image data of digital values obtained by photographing and recording them in a storage medium.
As is generally known, a novel electronic camera has recently been developed, in which optical images of a photographed subject are photoelectrically converted into image data of digital values by means of an image pickup device. These image data are compressed and recorded in a storage medium.
Recently, moreover, recording/reproducing devices that use disk-shaped storage media, such as hard disk devices, magnetooptic disk devices, etc., have been downsized, reduced in weight, and redesigned for larger capacities, and the way of incorporating the devices of this type into electronic cameras has been investigated.
Since these recording/reproducing devices are provided with a rotating unit for rotating a disk, power consumption is a critical problem to them. The rotating unit consumes much power especially during starting operation in which the disk in a stationary state is caused to reach a fixed steady rotational speed.
In view of the problem of power consumption, therefore, it is to be desired that the rotating unit should not repeat start/stop operation with high frequency. However, the electronic camera requires obtained digital image data to be recorded in a storage medium with every shot.
Inevitably, therefore, the rotating unit is used in a manner such that it repeats the start/stop operation highly frequently. In consequence, it substantially dissipates power from the power source of the electronic camera, so that the life of batteries for use as the power source is shortened considerably.
The present invention has been contrived in consideration of these circumstances, and its object is to provide an electronic camera designed so that the frequency of repetition of start/stop operation of a rotating unit for rotating a disk for use as a storage medium can be lowered to restrain power consumption, and that digital image data obtained by photographing can be securely recorded in the disk.
An electronic camera according to the present invention comprises first recording means for recording digital image data obtained by photographing in a semiconductor memory, detecting means for detecting the attainment of a predetermined value by the residual storage capacity of the semiconductor memory, and second recording means adapted to be rotated to transfer to and record all the digital image data stored in the semiconductor memory in a storage medium having a storage capacity larger than that of the semiconductor memory, in accordance with the result of detection by the detecting means.
According to the arrangement described above, all the digital image data stored in the semiconductor memory are transferred to and recorded in the rotatable storage medium having the capacity larger than the memory capacity when the predetermined value is reached by the residual storage capacity of the memory. Thus, the frequency of repetition of start/stop operation of a rotating unit for rotating a disk for use as the storage medium can be lowered to restrain power consumption, and the digital image data obtained by photographing can be securely recorded in the disk.
Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinafter.